基于增的LiMn2O4正电极用于快充金属电池的快充电池
Weihao Zeng1, Fanjie Xia1, Juan Wang1
1State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan, Hubei, China.
Nature communications
|August 27, 2024
概括
研究人员通过添加低价值离子来增强氧化物 (LiMn2O4) 用于快充电池. 这种度增加的材料可以实现1000个循环,保持80%的容量,从而实现快速充电.
科学领域:
- 材料科学 材料科学 材料科学
- 电化学 电化学 电化学
- 固态化学 固态化学
背景情况:
- 快速充电,非水性基电池对于实际应用至关重要.
- 氧化 (LiMn2O4) 提供了有利的离子扩散,但患有低速率能力和结构降解.
- 高电流导致传统LiMn2O4.4.的容量衰减和材料分解.
研究的目的:
- 为了提高LiMn2O4的速度能力和循环稳定性,用于快速充电应用.
- 为了研究通过阴离子兴奋剂增加对LiMn2O4性能的影响.
- 为非水性电池开发一种稳定,高性能正极材料.
主要方法:
- 合成了一种增加的LiMn2O4材料,添加了五倍的低价值 (LiMn1.9Cu0.02Mg0.02Fe0.02Zn0.02Ni0.02O4).
- 在非水性金属硬币电池配置中测试了材料.
- 使用先进的表征技术分析结构变化和离子运输机制.
主要成果:
- 增加的LiMn2O4材料在1.48 A g-1 (4分钟充电) 时实现了1000个循环,在25°C时保持80%的放电能力.
- 的增加导致了阴离子乱,局部结构收缩,扩大了LiO4空间,并增强了Mn-O共价性.
- 观察到改善的离子传输和稳定的扩散通道.
- 在高电荷状态循环过程中的压力通过弹性变形得到缓解,防止结构降解.
结论:
- 五倍阴离子兴奋剂显著提高了LiMn2O4.4的电化学性能和循环稳定性.
- Entropy 工程是一种可行的策略,可以克服 LiMn2O4 对于快充电池的局限性.
- 开发的材料显示了需要高功率密度和长周期寿命的实际应用的潜力.
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